Restorative dentistry is an important market in today's dental industry. In particular, tooth repair with temporary and permanent crowns is a common procedure, typically requiring multiple dental appointments. Conventional technologies use liners, adhesives, pastes, two-part powder/liquid systems, preformed metal temporary crowns, and ceramic or porcelain/metal permanent crowns.
Among the problems associated with the conventional technologies are the need for multiple visits to a dentist if a customized dental article is desired. Conversely, if customization is not desired, the dental article used may have a less than desirable fit and/or appearance, e.g., a metallic finish, larger gaps between proximal teeth, significant color variations from natural teeth, etc.
Hardenable dental materials have been developed to address some of these issues. Examples of some of these materials are described in, e.g., International Publication No. WO 03/015720 (Karim et al.) and U.S. application Ser. No. 10/219,398 filed Aug. 15, 2002 (Karim et al.), both titled HARDENABLE SELF-SUPPORTING STRUCTURES AND METHODS. For the purposes of the present invention, “hardenable dental materials” are materials that are capable of being hardened to form dental articles such as crowns, etc.
Although these materials may address the issues identified with respect to conventional technologies, they raise issues of their own with respect to the manufacturing, handling, and packaging of dental articles constructed of such materials. Many of these hardenable dental materials may exhibit significant levels of adhesion during manufacturing. As a result, shaping and handling of the hardenable dental materials into dental articles as a part of the manufacturing process may present challenges.
Another potential issue raised with some hardenable dental materials is that the techniques used to form the hardenable dental materials into usable dental articles may contribute to or detract from the finished appearance of the dental articles. In other words, the hardenable dental material may exhibit an undesirable rough appearance due to less than desirable forming techniques and/or packaging.
In addition, although the exact shape of dental articles manufactured of the hardenable materials before final hardening may be adjusted, significant shaping of the materials may not be possible or desirable depending on the properties of the hardenable dental material being used. For example, the dentist may prefer that the materials be provided in a shape that is close to the final desired shape of the dental article—subject to some minor shaping to provide a more customized fit and/or appearance. By providing the hardenable dental materials in a form that is close to the final form needed by the dentist, the time required for the dentist to complete any given dental procedure in which the dental article is used can be reduced. Such forming, however, may exacerbate the problems identified in the preceding paragraphs.